[PhillyPhilly]

I’m begging for help at this point… my MHD wireless adapter literally just came in the mail and I just want this problem to end!

2008 335i N54… Mods are DCI, charge pipe/bov and just a few days ago I put on the VRSF catless DP and race exhaust with plans to go stage 2+. Before all this I put in index 12’s/coded them and new NGK plugs that were gapped. Put in eldor coils as well. Also replaced boost pressure sensor and crankshaft position sensor as those were my only codes.

Car ran much better but I’m still getting a misfire/hiccup when I go WOT. No limp mode/No nothing! Just that jerky stutter that makes me cringe! I just bought NGK one step colder plugs and I’m going to try and put them in before the tune and make sure they are properly gapped to .22… But if that won’t work what are my options? 1. Walnut blast 2. Clean or replace Vanos 3. Make a claim with third party warranty for a new DMI? Please man… any info or suggestions would be highly appreciated!

Updated 10-6

So I loaded the MHD stage 2+ tune and the colder plugs! Still stuttering and I was mistaken as it’s not a misfire but I’m losing power somewhere during WOT. LPFP? Video below!
https://vimeo.com/624987569?utm_sour...campaign=29220

[Saif2018]

Originally Posted by PhillyPhilly

I’m begging for help at this point… my MHD wireless adapter literally just came in the mail and I just want this problem to end!

2008 335i N54… Mods are DCI, charge pipe/bov and just a few days ago I put on the VRSF catless DP and race exhaust with plans to go stage 2+. Before all this I put in index 12’s/coded them and new NGK plugs that were gapped. Put in eldor coils as well. Also replaced boost pressure sensor and crankshaft position sensor as those were my only codes.

Car ran much better but I’m still getting a misfire/hiccup when I go WOT. No limp mode/No nothing! Just that jerky stutter that makes me cringe! I just bought NGK one step colder plugs and I’m going to try and put them in before the tune and make sure they are properly gapped to .22… But if that won’t work what are my options? 1. Walnut blast 2. Clean or replace Vanos 3. Make a claim with third party warranty for a new DMI? Please man… any info or suggestions would be highly appreciated!

If it's a misfire, you should have codes indicating this.


What's this hick up, can you describe it, any logs?

[PhillyPhilly]

Originally Posted by Saif2018

If it's a misfire, you should have codes indicating this.


What's this hick up, can you describe it, any logs?

No logs… I haven’t uploaded the MHD yet. Basically… When I floor it and the RPM’s rise and get towards 6-7k the car will just stutter one time and I always just let off the gas when it does. It’s like one random kind of violent shake and that’s it. When I drive regular it’s fine… only when I open that throttle.

[lookalikehuuh]

I once had strange issues with misfire like symptoms while getting into high boost. Turned out the injector seals were not properly seated by the dealership when they installed the index 12 injectors. I ended up buying the new seals and purchased the seal installation kit and that resolved the issue for me.

Did you perform the installation of the new injectors or was it done by someone else?

Also like Saif2018 suggested an data log uploaded to datazap.me would go a long way to showing up what the car does. Ideally the log would be of an instance where the issue is present.

[PhillyPhilly]

Originally Posted by lookalikehuuh

I once had strange issues with misfire like symptoms while getting into high boost. Turned out the injector seals were not properly seated by the dealership when they installed the index 12 injectors. I ended up buying the new seals and purchased the seal installation kit and that resolved the issue for me.

Did you perform the installation of the new injectors or was it done by someone else?

Also like Saif2018 suggested an data log uploaded to datazap.me would go a long way to showing up what the car does. Ideally the log would be of an instance where the issue is present.

The injectors were done by a BMW specialist shop in my area… customer car lot is always packed full with top of the line bmw’s and there reviews checked out so I chose them for the injectors to save some hassle.

Also, I’m pretty new to all this but I just got my MHD OBD2 wireless adapter and I’m waiting for one step colders to arrive. Once I purchase the Super license from MHD, the data logging capabilities will be available for me correct?? Along with showing if any codes are popping up too obviously…

[Cloverdale]

Have intake valve's ever been cleaned / walnut blasted? It's required for optimum mod performance in an N54 that old.

[PhillyPhilly]

Originally Posted by Cloverdale

Have intake valve's ever been cleaned / walnut blasted? It's required for optimum mod performance in an N54 that old.

Going on Monday to get a quote on a Walnut blast after the MHD tune/colder plugs are installed and the issue persists.

[Dave92N54]

Betting it's plugs. I once received 2 defective plugs. Car would run great, get into boost and it would misfire but never threw a code unless I just kept hammering it until it did.

[Saif2018]

Originally Posted by PhillyPhilly

No logs… I haven’t uploaded the MHD yet. Basically… When I floor it and the RPM’s rise and get towards 6-7k the car will just stutter one time and I always just let off the gas when it does. It’s like one random kind of violent shake and that’s it. When I drive regular it’s fine… only when I open that throttle.

If the stuttering happens only at high rpms, could be injectors but get MHD and read codes first to find out which cylinder and rule out plugs and coils by swapping them round first before going to injectors.

[PhillyPhilly]

Originally Posted by Saif2018

If the stuttering happens only at high rpms, could be injectors but get MHD and read codes first to find out which cylinder and rule out plugs and coils by swapping them round first before going to injectors.

Appreciate your input… Will def log and read the codes. However I DID replace the injectors already with brand new index 12’s, brand new spark plugs and brand new eldor coils. Like stated before I’m gonna try the colder plugs and set up my MHD to see what’s what.

[PhillyPhilly]

Originally Posted by Dave92N54

Betting it's plugs. I once received 2 defective plugs. Car would run great, get into boost and it would misfire but never threw a code unless I just kept hammering it until it did.

I’m hoping so buddy! I got NgK one step colders en route to my address so this week I’ll swap them out and see.

[Saif2018]

Originally Posted by PhillyPhilly

Appreciate your input… Will def log and read the codes. However I DID replace the injectors already with brand new index 12’s, brand new spark plugs and brand new eldor coils. Like stated before I’m gonna try the colder plugs and set up my MHD to see what’s what.

No worries mate, that's good coils and injectors should be fine then check the plug gaps as well, that can also be the culprit.

[_N54]

Post up a log. 3rd gear WOT from 2000 rpm all the way to at least 6500 rpm.

[PhillyPhilly]

Video

https://vimeo.com/624987569?utm_sour...campaign=29220

[BSM n54iS]

Log it!

[NoGuru]

Nothing to diagnose without the logs.
High Pressure Fuel pump could cause this stutter you describe too. Must have logs.

[PhillyPhilly]

Originally Posted by NoGuru

Nothing to diagnose without the logs.
High Pressure Fuel pump could cause this stutter you describe too. Must have logs.

I’d assume the logs need to be recorded when the studdering actually happens yes? Just did two pulls and no stutter.

[PhillyPhilly]

https://ibb.co/MGZF6n9

[PhillyPhilly]

https://ibb.co/0fvdLfD

[PhillyPhilly]

https://ibb.co/Hrs20hY

[NoGuru]

Sorry, I forgot you are new to this. Upload the logs to Datazap, its a free account and then you can share the logs. This way we can manipulate the graphs to see the relevant data.

https://datazap.me/u/noguru/1-2-logs...og=0&data=3-20

[PhillyPhilly]

Bro I’m sorry how do I post the map on here for you to see? I already uploaded it to datazap.